Applicant is the inventor of two piece fasteners comprising a grommet and a stud shown in U.S. Pat. Nos. 3,112,547 and 3,116,528 and an initially single piece fastener shown in a copending application Ser. No. 531,732 filed Dec. 11, 1974. In each construction the stud moves axially without rotation in order to secure or release the grommet.